1. Technical Field
The present invention relates generally to seat back adjustment mechanisms and more particularly to a seat back adjustment mechanism that enables a seat back to be locked in a plurality of forward fold-down positions or alternatively to be locked in a generally horizontal or fold-flat position.
2. Discussion
Vehicle markets such as mini-van and sport utility are extremely competitive and a focus for improvement by automobile manufacturers. Specifically, automobile manufacturers seek to improve the overall utility and comfort of the vehicles in these markets in pursuit of attracting and keeping customers. One important feature is a flexible vehicle interior. Flexibility, in this sense, refers to the interior""s ability to provide seating that may be modified to suit a particular customer""s needs. For example, a customer might desire the removal of a rear seat to provide increased cargo space, while maintaining a middle seat or seats for additional passengers. Additionally, a passenger might desire the seat back of a front or middle seat to fold down, providing a work space while traveling. As such, a passenger could place a laptop computer on the folded down seat back or use the folded down seat back as a small desk for writing or reading.
While providing flexibility, vehicle seats must also include features for maintaining an occupant""s comfort, such as the ability to recline a seat back to any one of a number of desired positions. A variety of seat back recliner and fold-forward adjustment mechanisms are commonly known in the art. However, traditional fold-forward adjustment mechanisms require significant force applied to the release mechanism for unlocking the seat back for forward folding. Often, the required force suddenly releases the release mechanism, resulting in a jolt to the operator as the operator""s applied force overcomes the binding force of the release mechanism.
Therefore, it is desirable in the art to provide an improved release mechanism for a seat back recliner and fold-forward adjustment mechanism which overcomes the disadvantages discussed above. The improved release mechanism should enable an easier operator actuation thereof, without the associated jolting of traditional mechanisms.
Accordingly, the present invention provides an adjustment mechanism for a vehicle seat including a quadrant, an arm rotatably supporting the quadrant, a locking member slidably supported by the quadrant and selectively engaging the arm for locking the quadrant in a plurality of fold-forward positions relative to the arm, a cam plate rotatably supported by the quadrant for selectively biasing the locking member into engagement with the arm, and a gear assembly rotatably supported by the quadrant for actuation of the cam plate. The gear assembly provides a gear reduction for reducing the operator input force required to disengage the cam from the locking member when in a locked position. Preferably, the gear assembly includes a first gear plate rotatably supported by the quadrant and a second gear plate in meshed engagement with the first gear plate and in operable communication with the cam plate for selectively imparting rotation of the cam plate.
Additional advantages and features of the present invention will become apparent from the subsequent description and the appended claims, taken in conjunction with the accompanying drawings.